Selection of thermodynamic data for a novel carbothermic smelting process for aluminum

Abstract

For the carbothermic production of aluminum, thermodynamic data are required for the condensed compounds and gas phase involved in the Al2O3-C or Al2O3-Al4C3 systems. The data for Al2O3(s, l), Al4C3(s), CO(g), C(s, g), Al(s, l, g), Al2O(g) and AlO(g) in different databases is in accord. For a novel carbothermic aluminum smelting process, currently in development, the published JANAF Thermochemical Tables were selected for calculations. However, the JANAF Tables do not include data for oxycarbides. Thus a literature review was conducted. Data from different sources was collated and found to be in accord for Al4O4C over the 1,600–2,200 K temperature range. These data, together with the data from JANAF Tables, agree very well with the experimental results obtained during the carbothermic process. However, a commercially available computational thermodynamic software package called HSC provides results which contradict the experimental results obtained, while its thermodynamics data is also significantly different from other data available in the literature.